Signal type torque indicating wrench



INVENTOR. 7' 74N /VQA/ /754 BY v I Ill. I

1f iiil if@ k a s. s lNv/wLEIm-L N June l, 1948.

L iii/wey:

Patented June l, 1948 oFF 2,442,359Y SIGNAL TYrE 'rolmvlrrremmer-11s.G4 ENCE v l l (Granted under. the act of'March 3,^1,88321S 1 amended April 30, 1928,; 37010,. G, 7,57)

Tnerinvention described herein maybe manuiactureelV and'used'b'y o'rfor tleGove'rnment for governmental purposes, withoutftlre payrnentto :ne ofany royalty thereon.u

invention relates 'to improvements in torque :indicating wrenches of the type disclosed infrny copendingapp'lication Serial'fNo. 544,127, led July` 3,Y 1944, Wheiein'a'signal'means is incorporated responsive 'to flexre of fan'element of tlinlwr'encn under'a predetermined applied torque a.

'Torque indicating Wrenches-are per se-old in the art and in onelform of construfitiori of YWhich I armlaware, the peint' at whichthjindianng mechanism'l4 beconies operative ti'ndica'telthe applied torque is adjusted by varying the 'effective lengthhoia1 flexureorbeam nerr'rbfer which transmits-the torgue'irom alrandle'to' a 'Werk head. Iliis form ofjconstruction "is satisfactory 'where the torque rangei'ssrnall but reduiresan eiicessive lengtnof Wrench -wl'ere 'the torduefrange is large, such .as is Yencour;tered"in the aircraft eld. In my',copendingY application, "torque indicating Wren'mjes` are c'iisclosed'ir'r vvlich' the operating point of 4`the torque indicating signal systen'is changed Vasdesredb'y initial'variation of the spacingy offelectrical controlling contacts, Vrather thanibyjvarying the length ofgtlie'ilexureflmeinber, a lost motion travel' ofvjtheJ handle relative to the fleXure member being empleyedl to' vary thefspac'- lng.

In. accordance with the present invention, the

Apvo'int'lof, indication of the applied'trdileI n'ijay be sin aforce'bit. The-free` end 311.01 flexureelement 3 is disposed' with kslightclearance or a sliding rit through thethroatl ofthe'. stress applying ring 1 Wher'ebytorque. stressesv applied to handle 5 are transmitted to exurejelement. A contact rod 9 is rigidly supported within'flexure element 3, concentrically spaced; therein, and! extending. bevond the tubular, portionthereof, and having` a free end 9a extending into a sleeve IIL` Sleeve ID. is supported within*` body. l for.x reciprocal movement relative tothefree. endya of oontact rodi!` and, is a-compositaotthree relatively securedsleeves` Illa, I/Ilboand.t Inc. 'Sleeve Illav is providedwth' an externaliperipheral. groove. 2.3; sleeve I 0b is composedof an insulating mate.- rial: and Ysleeve weis providedwth an internal tapered surface I2.; The free-,end 9a of, contact rod 8 may be,considered,as-stationary relative to the torque. axis of thework head- 4 whereby movementOf the handle 5 .ina torque applyingV direc.- ton causes exure. of flexure; element 3 While bringing the tapered surfaceQ Ilintoengagement with. thefreeend 9a OffoontaCt-rodS-,for a, Purpose to be y describeil.v Qbvioucsly, the relation holds true. althoughv the Wrench as --a wholemay be rotating aboutV the torque axis,- of -work head 4. The recipkror-ral.-movernentlof,v sleeve I Il is obtained by rotaryv adjustment ofl a sleeve I,3vsupported on body between shoulder. I4 thereon and afcollar I5; secured to` -bodyI as bya screw IISt Aratchet coacti'on indicated generallyat I I is provided between -abutting*edges o f,-s1eeve.`|'3 and collar 4 I lfor. the f'purpose. of. 'securing sleeve I3tat any desredan'gular position; A scalejfl calibratedy ,in torqilefunits` a knurledz surface I9`a're provided on th'eexterior of the sleeve,z I3. An indexmarklon body] coastsA with the scale ls vfor;eor'ivenien'eje insetting thewrench to 'signalat' aY desired'aDplied `torlcglue-`4 Sleeve Y I 3 isgpro.- videdwithjan internalspiral .groove 2j, coacting with', spherical bearnesf 2.2,' roteiellyv Seemed! in the peripheral groove '2.3 provided] ext@mailyA on sleeve` Illa. Spherieal bearings l 2.2r are nain tained in av diannetric'allyl oppose'drelationsllip ,by longitudinal slots' 24 cut'through the Wall' of body I It Willbe appreciated'that.rotation of sleeve I3 produces; by yvirtueof spiral groove'ZI, a longitudinal tliru'st on spherical' bearings 22, the tlirust 'beingr transmittedtnerethrough`to sleeve I 0 by means of "peri'pheralgroove' 2 3 kwhereby said sleeve` Ill'can be reeiprocatedfina direkztion depending' upon the direction of rotation ofsleeve A spring 25 is compressively stressedbetween a recessv26 inthe 'outer 'faeef of sleeveY Ille and-4a cup ports 30, Vsleeve 3|,

21 in electrical contact with the center terminal of a signal lamp 28. Signal lamp 28 is threadedly secured within a housing 29 having ports 30 and being slidably disposed within a colored, translucent plastic sleeve 3I. 4 l Y Sleeve'3l-V mayj be permanently secured within handle 5, if desired. Acap 32 abuts the'outer extremity of the housing 29 and electrically contacts Y 4 Y torque within the upper and lower limits of th torque range.

Having thus disclosed my invention, what I claim Vas new and desire to protect by United States Letters Patent is:

1. In a torque .indicating wrench, a handle member for applying la torque fonce, a ilexure i member for transmitting said torque t-o a'work the center electrode of a dry cell 3,5. The negative f casing electrode of dry cell 34 is grounded through a spring 35 and an end cap 3E. The positive cen'- ter electrode of dry cell 34 is electrically insulated from ground by means of insulating Sleeve Illb Vhead and ,adapted for exure under'torque load,

av pivotal relationship provided between said members, torque predetermining means for energizinga signal in response to application of a Y predetermined torque comprising initially space- Yand sleeve 3l. It will be apparent from the foregoing that a relative angular movement between the contact rod 9 and sleeve I9, whereby a contact is produced between the free end 9d and the tapered surface I2 of sleeve Ic will complete a circuit lighting the signal lamp 28, the current assumedlystarting at the positive center terminal of battery 34, and passing, respectively, through cap 32, housing v29, signal lamp 28, cup 21, spring 25, sleeve 10c, contact rod'9, flexure member 3, body I, handle, end cap 36, and spring 35, to the negative casing terminal of battery 1 3A. Rays from signal lamp 28are visible toY an operator through and ports 323V provided in handle 5.1 Y i In operation, sleeve I is reciprocated by rota- VtionrofsleeveY I3 to some position wherein the free end 9a of contact rod 9 has a particular concentric spacing relativeA to some adjacent portion of the tapered surface I2 within sleeve IIlc, the specic radial distance depending on the degree of rotation of sleeve I3 as determined by indicium of the scale I3, As the handle 5 has torque force applied thereto, the throat 8 of stress applying ring] will be brought into abutment ,withV the' free end 3a of the'ilexure member 3 by virtue of the pivotal relationship provided at 2 between body I and flexure element 3. The torque stress is thus transmitted to'flexure element 3 causing deflection thereof, contactl rod 9 being relatively 1 Vinflexible and sufficiently spaced from the surrounding internal bore of flexure member Vil as not to lbe aiected by said deection.

With the flexing of flexureelement 3, a simultaneous decreasing of thejdistance between the free end 9a of contactrod 9 and an adjacent portion ofthe tapered surface I2 of sleeve I Ec occurs ultimately producing electrical contact therebetween, whereby a circuit will be completed through` lamp 28, the illumination thereof being visibleto the operator, 'all as heretofore described. Y i Y H Itwill be evident from consideration of the structure that the position shown for sleeve IllV irl-.Figure l corresponds to a low torque, since Va relativelysmall deflection of flexure element 3 will occur prior to the occurrence of an electrical contactbetween the free end 3a of contact rod 9 and an adjacent portion of the surrounding able elements Vwherein a rst element is substantially secured against motion relative to said work head when torque VVis applied thereto and comprises a'rod having a free end, a' second element comprising an internally tapered sleeve encompassing said free end and being axially adjustable relative thereto whereby an initial concentric Vspacing is provided therebetween, said internally tapered sleeve being angularly movable relative.V to said free end in response to torque applying motion of said handle'member, contact between said free endand the surface of the internal taper of said sleeve being operative to energize said sig-V nal, whereby errergizationethereof is responsive to a degree of torque force proportional to a degree of fiexure of said ilexure membenas pre-Y determined by the initial concentric spacing provided by axial adjustment between said free end and Vsaid internallyV tapered sleeve. Y

2. A torque indicating wrench comprisingl a handle member having a cylindrical handle portion securedl to a cylindrical body portion, a generally tubular flexure member` within said body portionY pivotally related thereto and having a protruding end adapted for attachment to a work head, torque predetenmining means comprising a contact rodl secured to said flexure member and havingV a free Vend extending therefrom, an in-Y ternally tapered sleeve within` said handle member and axially adjustablerelative to said free end, said free end protruding into'the internal taper thereof whereby an concentric variable spaced relationship is provided, said internally tapered sleeve being disposed for angular movement with said handle portion relative to said free Y end whereby contact between said free end and the surface of said internal taper occurs in response to torque applying motion of said handle member and is operative `to energize a signal;

' the degree of said motion being predetermined tapered surface I2 provided Vin sleeve Iilc. Con- Y.

versely, whenksleeve I0 is at the extreme righthand position, -as related to the view shown on Figure 1, nthe concentricspacing'between free end 9a and ani-adjacent `portion of the tapered surfalce I2 will-be relatively large whereby a greater deflection vof flexure element 3 willvbe required to produce electrical contact, corresponding to a high torque. Accordingly, the degree of ilexure ofthe exure element` 3 is determined by the pc' `Vsitionof sleeve I ll relative to thefree end 79a for the purpose of realizing a. signal at Va desired by the initial concentric spacing provided between said free end Vland said internal surface and `corresponding to a predeterminedtorque.

3. In a torque indicating wrench, a vhandle member for applying -a torque and a ilexuremember `connected thereto for transmitting said torque toY a work head, Vtorque predetermining means for energizing asignal in'responseto application of a predeterminedA torque including a pair Vof contact elements disposed vfor relative motion to eiect lengagement therebetween in response to torque applying movementofsaid han-V dle membenrneans whereby one of said elements is held substantiallyY stationary relative to` said work head during A torque applied Y movement' thereof and means whereby the other of said 4eleYAY ments is movable with said handle Vrmemberrdu-ring torque applying movement thereof, one of Vsaid elements having altapered contact surface, i

means for adjusting said Velements relative to each other so4 astoprovide an initial spacing Y therebetween by virtue of an approach or reces-VV sion of said tapered surface relative to the other Y* element as determined by the gradation of taper and the direction and degree of adjustment, the arrangement being such that engagement between said elements occurs at predeterminable points on said tapered surface, whereby the torque transmitted through said flexure member is manifested by energization of said signal upon occurrence of contact between said elements.

4. In a torque indicating wrench as set forth in claim 3, wherein one of said elements comprises a rod having a free end land the other of said elements comprises a sleeve slidably disposed relative to said free end and having an internally tapered bore encompassing said free end whereby an initial concentric spacing therebetween is provided by relative axial motion between said elements.

5. In a torque indicating wrench as set forth in claim 3, wherein said ilexure member has a relatively inflexible portion at the point of pivotal relationship with said body member, and said contact rod is secured at one end thereof to said relatively inflexible portion and is disposed internally oi said flexure member in concentric spaced relation thereto.

6. A torque indicating wrench comprising, a handle member having a relatively movable work head attached thereto. a tlexure member oi tubular form attached to said work head. spaced abutment means on said handle member engageable with said nexure member to transmit torque from the handle member to the work head. signal actuating means including an electrical circuit closing element secured to said work head vand extending axially through the tubular flexure member, an electrical contact element secured to and adjustable longitudinally of said handle member for engagement by said circuit closing element, 'and the contact face of said contact element being of tapered form for adjustment of the spacing between said elements in the no-load condition of said exure member.

7. A wrench structure as recited in claim 6, wherein the electrical contact element secured to and adjustable longitudinally o! said handle member comprises a sleeve slidable in a recess within said handle member and said sleeve being adjustable by means of a rotatable sleeve surrounding a portion of said handle member, tcgether with means to convert the rotatable movement of said rotatable sleeve to a sliding movement of said slidable sleeve.

8. A torque indicating wrench comprising, a handle member having a relatively movable work head attached thereto, a. ilexure member attached to said workV head, spaced abutment means on said handle member engageable with said flexure member Ito transmit torque from the handle member to the work head, signal actuating means including an electrical circuit closing element secured to said work head, an electrical contact sleeve having a conical inner face adapted to be contacted by said circuit closing element to close an electrical signal circuit, said sleeve being slidably mounted in a recess within said handle member, a rotatable sleeve surrounding a portion of said handle member, means to convert the rotatable movement oi said rotatable sleeve to a sliding movement ci said slidably mounted sleeve, and means on said rotatable sleeve and said handle to gauge the relative positions of each of said sleeves with respect to said handle member.

MARK HA'I'IAN.

REFERENCES CITED The following references are of record in the file oi.' this patent:

UNITED STATES PATENTS Number Name Date 2,225,420 Mandi Dec. 17, 1940 2,250,941 Zimmerman July 29, 1941 2,289,238 Brunelle July 7, 1942 2,303,411 Van Horn Dec. 1, 1942 2,320,023 Zimmerman May 25, 1943 2,371,901 L'ivemnont Mar. 20, 1945 FOREIGN PATENTS Number Country Date 675,755 May 16, 1939 679,042 Germany July 27, 1939 

